High voltage bobbin of fly-back transformer

Abstract

Disclosed is a high voltage bobbin of a fly back transformer for outputting high voltage. The high voltage bobbin of the invention comprises a bobbin body having a central hole for receiving a low voltage bobbin wound with a low voltage wire; input and output terminal sections integrally formed in upper and lower portions of the bobbin body and mounted with pluralities of input and output terminal pins; a plurality of insulating film layers wound on an outer surface of the bobbin body; high voltage wires each wound between two adjacent ones of the insulating film layers; and input and output hooks integrally formed on the outer surface of the bobbin body. The input hook catches a first one of the high voltage wires before the first wire is wound on the bobbin body, and the output hook catches the first wire wound on the bobbin body before the first wire is extended to the outside. The invention excludes winding a first insulating film on the high voltage bobbin before winding a first wire on the high voltage bobbin in order to save fabrication cost as well as decrease the number of process steps thereby enhancing the competitiveness of the high voltage bobbin and thus the fly-back transformer.

1 . A high voltage bobbin of a fly back transformer for outputting high voltage, comprising: 
 a bobbin body having a central hole for receiving a low voltage bobbin wound with a low voltage wire;    input and output terminal sections integrally formed in upper and lower portions of the bobbin body and mounted with pluralities of input and output terminal pins;    a plurality of insulating film layers wound on an outer surface of the bobbin body;    high voltage wires each wound between two adjacent ones of the insulating film layers;    input and output hooks integrally formed on the outer surface of the bobbin body, wherein the input hook catches a first one of the high voltage wires before the first wire is wound on the bobbin body, and the output hook catches the first wire wound on the bobbin body before the first wire is extended to the outside.    
   
   
       2 . The high voltage bobbin of a fly back transformer as set forth in  claim 1 , wherein each of the input and output hooks has a tapered configuration defined by a lower surface integrally connected by one end with an outer surface portion of the bobbin body and an upper surface contacting a lower surface portion of the insulating film, wherein the distance between the lower and upper surfaces gradually decreases toward a front end of each of the input and output hooks so that the lower surface meets the upper surface of the front end.  
   
   
       3 . The high voltage bobbin of a fly back transformer as set forth in  claim 1 , wherein the input and output hooks are formed on a parting line between upper and lower molds for molding the bobbin body.  
   
   
       4 . The high voltage bobbin of a fly back transformer as set forth in  claim 3 , wherein the input hook on the parting line has a front end oriented counter to a winding direction of the high voltage wires, and the output hook on the parting line has a front end oriented in the winding direction of the high voltage wires.  
   
   
       5 . The high voltage bobbin of a fly back transformer as set forth in  claim 3 , wherein the input and output hooks are formed on the parting line which is formed perpendicularly to the input and output terminal pins connected with both ends of the first high voltage wire.  
   
   
       6 . The high voltage bobbin of a fly back transformer as set forth in  claim 1 , wherein each of the input and output hooks has an arc-shaped upper surface which is formed at a radius of curvature substantially equal to that of the outer surface of the bobbin body.  
   
   
       7 . The high voltage bobbin of a fly back transformer as set forth in  claim 1 , further comprising upper and lower triangular clearances formed respectively in interfaces between the bobbin body and the input and output terminal sections for closely contacting the first high voltage wire with the outer surface of the bobbin body, the first high voltage wire being caught by the input and output hooks.  
   
   
       8 . The high voltage bobbin of a fly back transformer as set forth in  claim 1 , further comprising a plurality of insulating film-contacting blocks formed radially on the outer surface of the bobbin body having the input and output hooks, to a predetermined interval.  
   
   
       9 . The high voltage bobbin of a fly back transformer as set forth in  claim 8 , wherein each of the insulating film-contacting blocks has an upper surface which is formed at a radius of curvature substantially equal to that of the outer surface of the bobbin body.  
   
   
       10 . The high voltage bobbin of a fly back transformer as set forth in  claim 8 , wherein each of the insulating film-contacting blocks has an uppermost surface which is formed to a height substantially equal to that of an uppermost surface of each of the input and outer hooks.  
   
   
       11 . The high voltage bobbin of a fly back transformer as set forth in  claim 8 , wherein at least one of the insulating film-contacting blocks is formed wider than the input and output hooks to function as support points in fusion of terminal ends of the insulating films which are completed of winding.